Facing the increasingly serious problems of energy shortage and environmental degradation, an electric vehicle such as an electric automobile and an electric motorcycle is widely concerned for its advantages, for example, low energy consumption, zero emission, low noise, high energy efficiency, simple structure, and ease of maintenance. However, travel range of the electric vehicle is generally short due to its limited power battery capacity, which causes inconvenience in daily use. To avoid the situation that the electric vehicle is not able to travel due to low power of its power battery, a driver of the electric vehicle need to know the remaining travel range of the electric vehicle, i.e., distance the electric vehicle may further travel, so as to charge the power battery of the electric vehicle in time, or choose a reasonable driving mode and travel path.
Estimation of remaining travel range of the electric vehicle includes two parts: estimation of remaining available energy of the power battery, and estimation of average energy consumption per kilometer of the electric vehicle. Thus, the remaining available energy of the power battery becomes gradually a state parameter of the power battery that a Battery Management System (BMS) must report to a Vehicle Control Unit (VCU).